She's a Bluebelle, which I believe is a RIR x Marans cross. I expect her lovely dark brown 'scarf' round her hackles comes from the RIR genes. I've never had one before, and had heard that they're rather shy birds, but Violet is quite different, races to greet me when I go in the run, nibbles any bits she can get at (ouch - bare toes this morning in plastic slippers!) and doesn't mind being touched. Looks like a definite bid to be Top Hen .

Our Bluebell was all blue Marigold and very shy, but our Copper/Blue Marans was near identical to Violet and a very forward little girl. Of course the French breed standard is with feathered feet. See if you get brown eggs?

It's long been a mystery to me why a zillion websites say that the Bluebell is a RIR x Maran cross. Even if the Maran in question was a Copper Splash Maran this would give blue chicks but they would not be sexable at hatching and so would not appeal to the commercial boys and girls.
And RIR x Cuckoo Maran would be sexable at hatching but none of them would be blue.
Beats me!

I don't know anything about them but like you, am just quoting what I've read. It does seem strange to me that crossing a deep red bird with a fairly dark blackish one would produce such a lovely laced pale grey. However, they're supposedly good layers, which is the main thing, and my Violet is evidently quite a character!

OK, here's another management question. My object is to eliminate any worms my new hybrids might have brought in, as far as possible, to get them off to a good start, and then to manage the environment so worms never come back.
They had been living in a large barn on deep straw with dozens of others the same age and of mixed breeds. The drinkers and feeders looked clean but of course the floor was fairly dirty, unavoidable. They had been treated with Vermex on the first 3 days of each month and hadn't come into contact with any older birds, though I expect there may possibly have been worm eggs in the floor of the barn They are now in a completely clean run, with a new membrane over the floor, covered with fresh Aubiose, so no possibility of scratching up and eating earthworms etc. All surfaces and equipment have been jet washed and disinfected, the run is roofed and the mesh is too small to let in wild birds or vermin. The day they arrived I started them on Flubenvet, in a 500g. warm mash of mixed pellets, sunflower seeds, corn and mealworms, and observed all of them eating it greedily and cleaning the plate. They have normal pellets when they've finished the mash. They're now on Day 3 of the Flubenvet and I'm going in several times a day to poo pick thoroughly. All poos look normal today, though there were more caecal poos yesterday than usual, perhaps because they were settling in.
Do you reckon that they will be worm-free at the end of the week? Or what about if I treat them again in 3 weeks' time? If they could become worm-free, and live in a run with no chance of picking up any worm eggs, would they ever need worming again?

In theory the run should be worm free but I don't know if eggs survive for long periods outside. We don't worm ours now unless there is a potential problem indicated by their poos. As I may have mentioned before, we worm with Olive Oil and Flubenvet 'shots' only on days 1 & 2 and again on day 7 to kill hatched eggs- works well for us.

We have notice two types of caecal poos- foamy yellow sludge when excited but usually a brown fine smooth sludge which I think is a release of stored digestive enzyme. I say that as after Avipro treatment they do it a lot.

My own take on it, in addition to anyone else's, is that free worm eggs degrade very quickly when outside the host - chicken, mollusc, earthworm etc. When counting them they are desiccating, degrading and broken in a sample just a day or two old. Exposed they last only minutes. But that is enough to be passed around, of course, in droppings or in worms or snails.
Egg counts drop to zero a few days after a week of flubenvet. I have assumed that this is because the worms have been killed and it takes a while for the eggs released as they break up to work their way out. Whether those eggs are viable? I suspect they will have been damaged by the flubenvet and not viable but don't know for certain.
As we all know, common chicken worms are so prolific in the environment that excluding them completely and permanently would require commercial unit style bio security. But it is also about the rise in worm population.
A chicken can have low counts of eggs in poop for several months and be pooping normally, fit and well. But then if they are re-ingesting eggs from several birds or eating earthworms or snails (or generally pecking around outside) the population can rise suddenly and become a problem (usually quite a serious problem by the time there are and outward signs)
So I think you could extend the time between needing to worm by a lot with reasonable precautions but it would take extreme measures to keep them out permanently.

I agree with all you say, Rick - but am still wondering whether, if my chickens are kept in a worm-free enclosed run and don't peck around outside, eating earthworms snails etc, where would the worm eggs come from if the chickens didn't have any to start with?
I'm not paranoid about worms, and this query is largely hypothetical, but it might be an interesting experiment if I gave them a second dose of flubenvet in 3 weeks time to deal with any emergent worms, and then got them tested at 6 months and 12 months without further treatment.

If they don't get any access to open soil, worms and snails then they could go a very long time with no worm population at all. I wonder, if there is any value to the natural worm remedies then discouraging and prolonging the time before an exponential population rise may be it (along with minimising exposure.)
If you send off for testing I would make up the minimum 4 grams of sample (you would probably be sending at least twice that) from a few (just a couple in a flock of 5) separate poops but being careful not to crush the sample when collecting or in transit. Worm eggs are so fragile and a broken egg wont float and show up in the count.

... the best sample is a classic, semi- firm poop. An inbuilt problem with testing is you need to do it when the worm population is low or at most moderate. Runny poops are a bad sample and (even though that may be because the population is high and having an effect) will be unlikely to give a representative result, if any. Its not something you can do when you already think you may have a problem.